Motion picture mechanism



Jan. 4, 1944, .J. G. ZUBER MOTION PICTURE MECHANISM Filed Aug. 2,. 1940 R '61 W E T N U EZ V ME N H U 7 2 a W ATTY. I

'TiiED STATES PATENT. OFFICE 2,338,680 a p MOTION rrc'runs MECHANISM of Illinois Application August 2, 1940, Serial No. 349,565

3 Claims.

- invention relates particularly to the intert feed and light shutter mechanism of d. motion picture projecting machines, and mere particularly to intermittent feed and light ier mechanism of the skip feed motion and light interruption frequency type such as is :liplnsed in U. S. Patent No. 1,680,295, granted a gust 14, 1928, on application of. A. S. Howell, i Met-ion picture apparatus.

16 general object of the invention resides in the provision of a novel and effective intermittent feed and exposure shutter mechanism of the above type which permits of a comparatively low frequency feed cycle of the intermittent feed mechanism for the instant purpose of reducing the noise thereof and the tendency of such noise to interfere with sound reproduction and" which permits of the retention of a desirably high light interruption frequency. c

With this object in view, my invention consists in certain features of novelty in the construction, combination, and arrangement of parts by which said object and certain other objects, hereinafter appearing, are effected all as fully described with reference to the accompanying drawing, and more particularly pointed out in t the appended claims.

In the said drawing Figure 1 is a rear elevation of an intermittent feed and exposure shutter mechanism embodying my invention;

Figure 2 is a sectional view substantially on the line 2-2 of Figure 1; and

Figure 3 is an enlarged partial sectional view substantially on the line 3-3 of Figure 1.

Referring to the drawing, I designates an en closing frame forming a part of a motion picture projector frame, and a transversely disposed vertically extending film face guide plate 2 is secured on the frame and is provided with a light aperture 3 through which light from a suitable source passes for projection from a portion of a usual vertically disposed feed perforated film strip 4 retained against the guide plate for vertical movement by usual guide means not shown. See Figures 1 and 2.

A shaft 5 is rotatably mounted on the frame I on a horizontal axis to ,one side of and normal to the plane of the guide plate 2 by means of a suitable bearing partially shown at 6, and a second shaft 1 is rotatably mounted on the frame I on a horizontal axis parallel to that of the shaft 5 and at the side thereof remote from the plate 2 byameans of a suitable bearing partially shown at .t

A bushing 9 is secured on a projecting end of the shaft 1, and an axially bored member II is secured on the bushing 9 for rotation with this shaft. A'large spur gear I2 on th member II meshes with a small spur gear I3 on the shaft 5 whereby a plurality of revolutions of the shaft 5 is effected during one revolution of the shaft 1, the bushing 9 and the member I I, the ratio shown being two revolutions of the shaft 5 to one revolution of the shaft I.

A pair of studs I4 are secured on the frame I, as designated at I5, and are disposed in alined spaced relation on a vertical axis intersecting the axis of the shaft 5. A shuttle plate I8 is disposed in a vertical plane and the upper and lower portions thereof are provided with laterally disposed coaxial bored bearing portions I! which are engaged on the studs I4 for pivotal movement of the shuttle plate on the stud axis and movement therealong. See Figures 1 and 2.

The shuttle plate is provided with a central aperture I8 elongated transversely of its pivotal axis and forming opposed surfaces extending transversely of the pivotal axis of the plate in intermediate relation with the studs I4. A radial cam I9 is formed on the shaft 5 and is engaged in the aperture I8 and operates on said opposed surfaces to effect reciprocating film feeding and return movement of the shuttle along the studs I4 during rotation of the shaft 5. The shuttle plate has a vertically extending cam engaging portion 2I extending in parallelism with the pivotal axis thereof,'and an axial cam 22 formed on the member I I engages the portion 2I and operates thereon to effect oscillating film engaging and disengaging movement of the shuttle plate on its pivotal axis. The shuttle plat is provided with an arm 23 extending laterally in the plane thereof, and the outer end of this arm is provided with a tooth 24 adapted to extend through a vertical slot 25 in the guide plate 2 and engage usual feed perforations of the same.

As the cams I 8 and 22 are rotated in timed relation by reason of the meshing connecting gears I2 and I3, the cam I9 effects one reciproeating film feed and return movement of the shuttle plate with each revolution thereof and the cam 22 effects one oscillating film engaging and return movement of the shuttle plate with each revolution thereof and is adapted in its timed relation with the cam I9 to effect film engaging and disengaging movement of the shuttle plate in film feeding relation with but one of each plurality of feeding movements of the the film 4 for feeding shuttle plate. As shown, the film is advanced durin but one of each two revolutions of the cam I9 by reason of the two-to-on gears i2 and I3 connecting the cams I9 and 22.

A light interrupting disk shutter 26 is rotatably mounted, as designated at 21 in Figure 2, on the shaft 5 and consequently in coaxial relation with the cam IS. A large spur gear 28 is secured on the bushing 9 and meshes with a small spur gear 29 fixed with the shutter 25 whereby the shutter is rotated in timed relation with the cams l9 and 22 of the intermittent feed mechanism, above described, and at a greater revolution frequency than that of the cam 22, the ratio shown being one and one-half revolutions of the shutter to one revolution of the cam 22. By reason of the two-to-one gears l3 and I2 connecting the cams l9 and 22 and the one and one-half-to-one gears 29 and 28 connecting the cam 22 and the shutter, the shutter has a revolution frequency of one and one-half-to-two revolutions of the feed cam IS.

The shutter is provided with diametrically opposite spaced shutter blades 3| providing diametrically opposite light openings 32 therebetween, the blades 3| sweeping over the light aperture 3 in operative relation with the feed film 4. Accordingly, the shutter has a light interrupting frequency greater than the feed cycle frequency of the feed cam H, as shown, the ratio being a shutter light interruption frequency of three to a feed cam cycle frequency of two, thus attaining the object heretofore set forth.

While I have thus described my invention, I do not wish to be limited to the precise details described, as changes may be readily made without departing from the spirit of my invention, but having thus described my invention, I claim as new and desire to secure by Letters Patent the following:

1. In a motion picture mechanism, the combination with an intermittent strip feed mechations thereof, of a revoluble light interrupting shutter in operative relation with a strip fed by said feeding mechanism and adapted to interrupt light in diametrically opposite positions thereof, and rotatory means for rotating said shutter in timed relation with said feed mechanism at a revolution frequency of one and one-half to two revolutions of said feed member.

2. In a motion picture mechanism, the combination with an intermittent strip feed mechanism, comprising a revoluble feed member, a second revoluble member for rendering said feed member operative and inoperative to effect feed of a strip, and two-to-one gearing connecting said revoluble members to effect feed of the strip during but one of each two revolutions of said feed member, of a revoluble light interrupting shutter in operative relation with a strip fed by said feed mechanism and adapted to interrupt light in diametrically opposite positions thereof, and additional gearing for rotating said shutter in timed relation with said feed mechanism at a revolution frequency of one and one-half to one revolution of said second revoluble member.

3. In a motion picture mechanism, the combination with an intermittent strip feed mechanism comprising a revoluble shaft provided with a radial feed cam, a revoluble axial cam disposed in parallelism with said shaft for rendering said feed cam operative and inoperative to effect feed of a strip, and two-to-one spur gearing connect-- ing said shaft and axial cam to effect feed of the strip during but one of each two revolutions of said shaft, of a light interrupting disk shutter in operative relation with a strip fed by said feed mechanism and rotatably mounted on said shaft and provided with two diametrically opposite spaed shutter blades, and one and one-halfto-one spur gearing connecting said axial cam and said shutter for rotating said shutter in timed relation with said feed mechanism at a revolution frequency of one and one-half to one revolution of said axial cam.

JOHN G. ZUBER. 

